In manufacturing, for example, a semiconductor component or a flat panel display, a substrate liquid processing apparatus that performs a liquid processing on a film formed on a surface of a substrate (e.g., a semiconductor wafer or a liquid crystal substrate) with an etching liquid (processing liquid) is used in order to form, for example, a circuit pattern on the surface of the substrate.
For example, the substrate liquid processing apparatus, which is disclosed in Japanese Patent Laid-Open Publication No. 2013-93478, boils a phosphoric acid aqueous solution (etching liquid) at a predetermined temperature so as to prepare phosphoric acid aqueous solution at a predetermined concentration, and immerses a substrate in the phosphoric acid aqueous solution for a predetermined time so as to etch a film formed on the surface of the substrate. On the surface of the substrate, a silicon oxide film is formed as an underlayer, and a silicon nitride film is formed on the surface of the silicon oxide film. Meanwhile, when performing the etching, a desired resist pattern is formed on the surface of the silicon nitride film.